[LegalizeTypes] Add strict FP support to SoftenFloatRes_FP_ROUND. Fix mistake in SoftenFloatRes_FP_EXTEND.
These will be needed for ARM fp-instrinsics.ll which is currently
One of the getOperand calls in SoftenFloatRes_FP_EXTEND was not
taking strict FP into account. It only affected the call
to setTypeListBeforeSoften which only has an effect on some targets.